I’ve disabled all other plugins and switched to TwentyFifteen theme, still same issue. Slider seems to jump 2 slides when clicking next/previous. When I set “carousel” in settings, it still does a fade. I originally had the non-pro version installed and had the same issue, then I purchased the pro thinking it would get rid of the issue and it did not.

Hi Lucas, Can you please check after enabled pagination? To enable pagination go to Settings > General settings > and switch on Pagination.
You can check the demos at http://testimonial.gsamdani.me
I’ve tested with different themes and next/previous control working perfectly.